Variation in the reproductive cycle of Elminius modestus in southern Ireland

Abstract

The reproductive cycle of the Australasian barnacle Elminius modestus (Crustacea: Cirripedia) was studied at three sites within Whitegate Bay, Cork, Ireland over 15 months. At all three sites, there were seasonal trends in development of the male and female reproductive organs with, for example, the ovaries regenerating whilst eggs were being brooded. Throughout the year, significantly lower percentages of animals were brooding embryos at the site of a warm-water outfall than at another site nearby. The factors which may affect the reproductive cycle of E. modestus are discussed.